26

DU Journal of Undergraduate Research and Innovation

Volume 1, Issue 3 pp 26-38, 2015

Microbiological and Physico-Chemical

Quality of Groundwater at a Resettlement

Colony, Madanpur Khadar in Delhi, India

J. Kaur 1, S. Kaur

1, V. Dashora

1, Y. Chaudhary

1, P. Nijhawan

1, S. Saini

1,

M. Dabas2, K. Sharma

2, R. Aggarwal

3, V. Gupta

1, R. Singh

4, P. Pande

5,

S. K. Sharma3, S. John

1, R. K Gupta

1#

rgupta1965@yahoo.com, 1Department of Microbiology,

2Department of Computer

Science, 3Department of Hindi and NCC,

4Department of Commerce,

5Department of

Geology, Ram Lal Anand College, University of Delhi, Benito Juarez Road, New

Delhi-110021, India

ABSTRACT

Groundwater has been the main source of fresh water supply to a large number of

Jhuggi-Jhopri clusters and resettlement colonies in Delhi along the Yamuna River

Flood Plains generally referred to as Khadar. One such resettlement colony Madanpur

Khadar in South Delhi established in 2001 lacks the most basic amenities like safe

drinking water, sanitation and sewage disposal. There are many common complaints

of gastroenteritis, diarrhoea, jaundice, skin irritation, eczema and unpalatable quality

of water. Hence, the present study was envisaged to assess the microbial and chemical

quality of groundwater of the area by analysing it for the presence of coliforms (the

indicators of water-borne pathogens), Total Dissolved Solids (TDS), Conductivity,

Hardness, Chemical Oxygen Demand (COD), Manganese and Iron, the most probable

factors accountable for the above mentioned problems. About one fourth of the water

samples contained a high number of coliforms suggesting contamination of aquifers

with faecal matter, hence making it unfit for consumption. Similarly, high

concentrations of manganese and iron, beyond permissible limits as defined by the

Bureau of Indian Standards and World Health Organization, were found in 90% and

33% of water samples, respectively. All the water samples were classified as very

hard on the basis of their CaCO3 content, while 52% samples failed the desirable

limits of TDS. High content of organic matter, iron, manganese and coliforms of

water samples indicates the seepage of sewage from the overflowing drains present in

the proximity of the hand pumps and hence are responsible for the unsafe and

unpalatable quality of water. The water samples were found to be unfit for

consumption without passing through any of the treatment processes of disinfection,

oxidation and filtration.

27

Keywords: Groundwater, Metal related water discoloration, Microbial quality,

Physico-chemical parameters, Yamuna Flood Plains, Madanpur Khadar.

INTRODUCTION

Delhi designated as National Capital Territory (NCT) of Delhi in 1991 is spread in a

total area of 1483 square kilometres with a population of 16.753 million as per the

2011 Census of India (1). Considering the increase of population at the rate of 1.92 %

per annum in Delhi, it is expected to reach 18.069 million in 2015 and 20.264 million

in 2021 (2). The current potable water requirement for Delhi’s population in 2015,

based on 60 Gallons Per Capita Per Day (GPCPD) as per the norms of Central Public

Health and Environmental Engineering Organization, Ministry of Urban

Development, Government of India would be 1084 Gallons Per Day (GPD).

However, the total water treatment capacity and supply in the city since 2012 has

been stagnant at 848 GPD including all resources i.e. rivers, canals and under

groundwater (2). The fresh water (both treated and untreated) is made available to

81.3 % households by piped water supply system, whereas water to 5.3 and 8.4 % of

households is provided by Hand pumps and Tube wells, respectively (1, Figure-I).

Figure-I. Distribution of households supplied with different sources of water in

Delhi. Census of India 2011 (1).

This vast difference in the supply and demand of fresh water has resulted in the

unregulated overexploitation of groundwater aquifers affecting the groundwater level

and the aquifer’s recharge capacity.

28

Groundwater has been found to be contaminated with a large number of microbial

species including viruses (Table-I) which are responsible for gastrointestinal diseases

(3).

Table-I: Water-Borne bacterial, viral, protozoan and helminths diseases and their

causative agents (3), (5-6).

Agent Disease Agent Disease

Bacteria Virus

Shigella spp.

S. dysenteriae

S. sonnei

S. flexneri

Salmonella spp.

S. typhimurium

S. typhi

S. paratyphi

Escherichia coli

(O157:H7)

Campylobacter

jejuni

Vibrio cholerae

(O139)

Yersinia

enterocolitica

Mycobacterium

spp.

M. kansasi

M. avium

M. fortuitum

Aeromonas spp.

A. sobria

A. hydrophila

A. caviae

Legionella

pneumophila

Pseudomonas

aeroginosa

Helicobacter pylori

Clostridium

botulinum

Leptospira

Bacterial

Dysentery

Salmonellosis

Typhoid fever

Paratyphoid fever

Diarrhoea

Gastroenteritis

Cholera

Yersiniosis

Infections in skin,

lymph nodes and

GI tract.

Gastroenteritis

Legionellosis

Blood Infections

Gastric Ulcers

Botulism

Leptospirosis

Hepatitis A

Norwalk-like agent

Virus-like particles

<27 nm

Rotavirus

Poliovirus

Calcivirus

Hepatitis E

Adenovirus 3

Coronavirus

Hepatitis/Jaundice

Gastroenteritis

Gastroenteritis

Gastroenteritis

Poliomyelitis

Gastroenteritis

Jaundice

Pharyngo-

conjunctival fever

SARS

Protozoans

Giardia lamblia

Entamoeba

histolytica

Cryptosporidium

Microsporidium

Balantidium coli

Giardiasis

Amoebiasis

Cryptosporidiasis

Microsporidiosis

Balantidiasis

Helminthes

Schistosoma

Fasciola hepatica

Cercariae

Dracunculus

medinensis

Ascaris

lumbricoides

Enterobius

vermicularis

Echinococcus

granulosus

Schistosomiasis

Fascioliasis

Cercarial dermatitis

Dracunculiasis

Ascariasis

Enterobiasis

Echinococcosis

Cholera, bacterial dysentery, amoebic dysentery, typhoid, diarrhoea and jaundice are

some of the examples of water borne diseases. Diarrheal diseases alone are

responsible for more than 1.4 million deaths every year globally, out of which, 88% is

29

attributable to poor and unsafe water supply, sanitation and hygiene mainly in the

developing countries (4). A number of studies conducted in various parts of India

including Delhi have shown the presence of coliforms and faecal coliforms in

groundwater samples indicating the contamination of aquifer by faecal matter or

sewage (7-15).

The hydrogeochemical processes influence the chemical quality of water in aquifers

and are responsible for variations in water characteristics due to rock water

interactions and anthropogenic interferences (16). These variations are very much

apparent in the four different physiographical regions of Delhi: Newer Alluvium-

Yamuna Flood Plains generally referred as Khadar; Older Alluvium – East and West

sides of the ridge; Older Alluvium – Chattarpur alluvial basin and Quartzite rock

ridge - Extension of Aravali hills from southern part of NCT to Western Banks of

Yamuna (16-17). Yamuna Active Flood plain aquifer covers about 35 km along the

river Yamuna. The depth of water level in the Newer Alluvium is shallow at 35-70 ft

which reduces to 20 ft only during monsoon season and flooding of river Yamuna.

The physico-chemical quality of groundwater in flood plains in general reflects the

river water quality being classified as fresh water because of river bed recharge (16),

(18).

Yamuna Flood Plains on both the east and west sides have been occupied by either

unauthorised settlements like Jhuggi-Jhopri (JJ) clusters (21.9 %) or a few authorized

resettlement colonies (19). Madanpur Khadar is one such resettlement colony where

the basic amenities like safe drinking water and sanitation facilities are lacking (20).

The main sources of fresh water in this settlement are the privately installed hand

pumps (76.2%), packaged drinking water (13.8%) and MCD water tankers (10%)

(20).The water from hand pumps contained high particulate matter and foul odour and

turned yellow on storage as reported by residents during a survey conducted by Saini

in 2012 (20) and in our study. Some common complaints of ailments like frequent

gastric troubles (Gastroenteritis), diarrhoea, jaundice, typhoid, etc. in both children

and adults have also been reported from the households who used hand pump water

for drinking (22). In view of the above problems of unpalatable water and prevalence

of water borne diseases, it becomes pertinent to identify the reasons and sources

responsible for such a poor groundwater quality. Therefore, this study was enunciated

to determine the microbiological and physico-chemical properties of groundwater

used by inhabitants of Madanpur Khadar, a resettlement colony established in

Yamuna Flood Plains.

METHODOLOGY

Study Site:

Madanpur Khadar, a resettlement colony, was established in 2001 where people from

slums of Nehru Place, Alaknanda, Raj Nagar, etc were relocated by Government of

Delhi by allotting houses of 12 to 25 square meter area depending on their length of

stay in the slums. This colony is located on the west bank of river Yamuna in South

Delhi (Figure-II). It is surrounded by river Yamuna on the East, a NTPC water

treatment plant on the South and Agra Canal on the North and the West.

30

Figure-II. Map of Delhi showing Madanpur Khadar, the site of Groundwater sample

collection. Source: Google Maps

Sample Collection:

Hand pumps installed in front of houses were randomly selected from Block A3, A2,

A1 and B1 covering almost all the area. Twenty one water samples were collected in

two - one litre autoclaved screw capped glass bottles under aseptic conditions after

continuously running the hand pumps for about 10 minutes to dispose-off the stored

water in the bore well pipes. Water samples in one of the bottles were preserved by

adding a few drops of HNO3. Two samples from water treatment plants (reverse

osmosis treatment) maintained by private suppliers were also collected. Samples were

stored on ice in ice boxes and transported to the laboratory within 3-4 hours for

further analysis.

Microbiological Analysis:

All samples were analysed for the presence of total coliforms and faecal coliforms

following the APHA’s Standard Methods for the Examination of Water and

Wastewater, 2012 (23). Total coliforms were estimated by Multiple Tube

Fermentation test (MPN/100ml) and Membrane Filter technique. In the Multiple Tube

Fermentation test, water samples in volumes of 10 ml, 1 ml and 0.1 ml were

inoculated into tubes containing Lauryl Tryptose Broth (Hi-Media labs) with 0.02 %

Bromocresol Purple and inverted Durham’s tubes to check for acid and gas

production, respectively. The change in colour of broth from purple to yellow or

collection of gas in Durham’s tube was observed after 48 h of incubation at 37° C. In

the filtration method, 100 ml water sample was filtered through 0.45 μm pore size

31

membrane filters (Millipore). Filters entrapping any bacterial cells present in water

were transferred to Endo Agar (Hi-Media) plates and incubated at 37°C for 24 h. The

typical coliform colonies with red colour and metallic sheen developed on membrane

filters were counted. Thermotolerant Faecal coliforms were detected by transferring a

loop full of fermented medium from the positive Lauryl Tryptose Broth tubes to

Brilliant Green Bile Broth tubes having inverted Durham’s tubes. The collection of

gas in the Durham’s tube in Brilliant Green Bile Broth was observed as positive test

after incubation at 44.5° C for 24 h.

Physico-Chemical Analysis:

All samples were analysed for pH, Electrical Conductivity (EC), Total Dissolved

Solids (TDS), Total Hardness (TH), Chemical Oxygen Demand (COD), Iron-Fe (II),

Manganese-Mn (II) and Salinity. EC, TDS and EC based salinity were measured by a

KCl calibrated bench top Conductivity meter (Model TCM-15, TIMPL). COD, Fe and

Mn values were determined using Spectroquant cell test kits (Merck Millipore) as per

the manufacturer’s instructions. Hardness was estimated by EDTA Titration method

following APHA 2012 (23).

RESULTS AND DISCUSSION

Groundwater samples collected from hand pumps in Madanpur Khadar were

colourless, odourless and without any visible turbidity. However, during storage of

these samples in refrigerator, 60% samples developed yellowish brown precipitates

while in others white precipitate was generated. Similar details provided by the

inhabitants of the study area proved to be of great help in deciding the type of

analytical determinants. The results of all analytical parameters along with their

comparison with BIS 2009 standards for drinking water (24) have been presented in

Table-II.

Table-II. Summary of chemical and microbiological analysis of groundwater samples

in comparison with BIS standards, 2009 (24) for drinking water.

Parameters Minimu

m

Maximu

m

Avera

ge

BIS

Standard

Percentage

of samples

beyond the

permissibl

e limits

pH 6.7 7.4 7.1 6.5-8.5 Nil

Electrical

Conductivity

(μmho/cm)

556 982 767 1500 Nil

Total Dissolved

Solids (mg/L)

364 643 504 500 52

Hardness

(mgCaCO3/L)

416 676 509 200 100

Salinity 0.30 0.48 0.37 0.75 Nil

Chemical Oxygen

Demand (mg/L)

UD 114 17 10 24

Mn (mg/L) 0.04 1.04 0.56 0.1 90

32

Fe (mg/L) 0.01 1.82 0.40 0.3 33

Total Coliform/100

ml

0 1600 79 Absent 24

Faecal Coliforms - + NA Absent 9.5

The pH of water samples was in the range of 6.7-7.4 with an inclination towards

acidic or neutral pH in most of the samples. The pH values were within permissible

limits as prescribed by BIS 2009 (24) and WHO 2004 (4). The similar pH values with

7.2-7.3 average of water samples collected from Yamuna flood plains and other parts

of NCT Delhi were observed in other studies (16), (25-27) though a wide pH range

was seen in these studies. The pH variation of groundwater samples is the result of

geochemical equilibration, dissolution of minerals, neighbourhood mining sites and

waste contamination (28).

Electrical conductivity accounts for the concentration of ionized substances in water

and could directly be related to total dissolved solids. The EC values of water samples

varied from 556 to 982 μmho/cm with an average of 767 μmho/cm, much below the

permissible limits of 1500 μmho/cm (4). However, in a study conducted by the

National Institute of Hydrology, Roorkee in 2000 (25) of Yamuna Flood Plains from

Palla area to Okhla Barrage, 70% the water samples both post monsoon and pre

monsoon were found to have EC >1000 μmho/cm. In other parts of Delhi particularly

Dwarka sub-city and South and South-West of ridge, very high EC values (37,400

μmho/cm) have been observed in some samples (16). EC values of all water samples

were compared with TDS values (Figure-III). The correlation between EC and TDS

values of all water samples follows the Davis and De Wiest (29) method without any

outlier.

Figure-III. Relationship between Total Dissolved Solids (TDS) and Electrical

Conductivity (EC).

Natural waters have been classified on the basis of the concentration of total dissolved

solids (TDS) consisting of anions (HCO3-, CO3

-, Cl

-, PO4

-, NO3

- and SO4

--), cations

(Ca++

, Mg++

, Na+, K

+, Fe

++, etc.) and small amount of organic matter (29). In the

33

present study, the values of TDS of groundwater samples varied from 364-643 mg/L.

48% of the water samples contained TDS within desirable limits of 500 mg/L for

drinking water. However, TDS of all samples tested was within permissible limits

(1000 mg/L) for drinking water (Table-III). These TDS values are in contradiction to

the TDS values observed in water samples from Yamuna Flood Plains in which only

10% samples had TDS confirming the desirable limit (25). The entire water samples

tested in this study were found to be fresh on the basis of Davis and De Wiest (29)

classification, indicating the Yamuna River to be the predominant recharge source.

Table-III. Classification of Groundwater based on TDS (29).

Water Suitability TDS

(mg/L)

range

Percentag

e of

samples

Water

Type

TDS

(mg/L)

range

Percentag

e of

samples

Desirable for

drinking

<500 48 Fresh 0-1000 100

Permissible for

drinking

500-1000 52 Brackis

h

1001-

10,000

Nil

Useful for irrigation <3000 Nil Salty 10,001 –

1,00,000

Nil

Unfit for irrigation

and drinking

>3000 Nil Brine >1,00,00

0

Nil

The presence of divalent cations like Calcium and Magnesium and their HCO3 and

CO3 salts makes the water hard and defines the suitability of water for its different

applications. All the water samples studied were classified as very hard (Table-IV) on

the basis of hardness values which ranged from 416 to 676 mgCaCO3/L much beyond

the acceptable limits. Hardness of the two RO treated water samples collected from

the area was < 75 mgCaCO3/L allowing these samples as control markers of analysis.

Table-IV. Classification of groundwater samples on the basis of hardness (33).

Total Hardness as

CaCO3 (mg/L) range

Water Type and

Quality

Percentage of samples

<75 Soft Nil

75 - 150 Moderately Hard Nil

150 - 300 Hard Nil

>300 Very Hard 100

The use of very hard waters both for domestic and industrial purposes will result into

corrosion and scaling on utensils, heat exchangers, metal pipes in the distribution

system, etc. Very hard water on regular consumption have also been found to show a

temporary change in bowel habits and a laxative effect (diarrhoea) if it contains a

very high concentration of magnesium along with sulphate (30). Excess exposure to

very hard water has been suggested to exacerbate atopic eczema (31-32). The

complaints of skin irritation and eczema among inhabitants of Madanpur Khadar

(Survey in this study) could be attributed to the very hard groundwater quality used

for washing, bathing and other activities.

The reporting of groundwater samples of the study area turning turbid with yellowish

brown or white precipitate by the residents (20), prompted us to check for the load of

34

total organic matter (COD), manganese and iron. These constituents particularly Mn

and Fe remain solubilised under anaerobic conditions of groundwater and hence does

not show any change in the fresh water characteristics. However, during storage of

groundwater Mn and Fe get oxidized, precipitate as white or yellow-brown salts (rust

coloured silt) and turn the samples turbid (34-36). COD content determined by

potassium dichromate method was found to be very high in 24% of groundwater

samples. In these samples COD levels were above 25 mg/L, with 114 mg/L in one of

the samples, much above the permissible limits of 10 mg/L. In other samples COD

was below the detection limits of the Spectroquant Cell test kits (25 mg/L). Hence, the

presence of organic matter in other samples above the permissible limits of 10 mg/L

cannot be ruled out. These values for COD in groundwater samples were surprisingly

high as even the water samples collected from Yamuna River did not contain COD

more than 90 mg/L (37) when tested over a period of one year. This shows that the

source of such high organic content in water samples tested cannot be the Yamuna

Basin.

In addition to the high COD values, 90% of water samples contained Mn >0.1 mg/L

with the highest values of 1.04 mg/L in one of the samples. Similarly, Fe content in

33% of water samples was beyond the permissible limits of 0.3 mg/L with highest

concentration up to 1.82 mg/L. At concentration exceeding the permissible limits of

0.1 mg/L, Mn imparts undesirable taste and discoloration (38) and at values as low as

0.02 mg/L, it can form coating on water pipes that sloughs off as black precipitate

later (34). High levels of Mn up to 1.3 mg/L and 9.6 mg/L have been found in neutral

and acidic groundwater, respectively, in USA (39). Hydrogeological studies of

groundwater in Delhi have revealed high concentrations of Mn in the eastern part of

Delhi i.e. young alluvial regions attributing it to the anthropogenic activities such as

waste discharge from industrial units (16), (26). Though the health risks of human

exposure to high amounts of Mn from drinking water are substantially low as most

adults consume Mn between 0.7 and 10.9 mg/day in the diet (40), its effects on

colour, turbidity and taste of water are much more adverse, making the water

unpalatable.

Analogous to high Mn content of water samples studied, high iron concentrations may

also result into turbidity and discoloration on storage. Iron levels above 0.3 mg/L in

water may stain laundry and plumbing. The chances of any health risk from high iron

waters are minimal as the concentrations of iron are too low as compared to the iron

intake (10-14 mg/day) from food sources (41).

Total coliform count in 24% of water samples exceeded the prescribed standards

which stipulate complete absence of coliforms in drinking water. Faecal coliforms

were detected in two water samples indicating a direct correlation between the

microbial contamination of groundwater and sewage access to the aquifers. The well

fields of Palla area (North Delhi) existing in the Yamuna Flood Plains are being used

to extract groundwater for fresh water supply to some parts of Delhi. A study on the

microbial quality of water in these wells showed that more wells were contaminated

with coliforms during post-monsoon season as compared to pre monsoon period (15).

The high water table in the study area makes the shallow groundwater aquifers

vulnerable to contamination by sewage percolation from the surface. Significantly

high concentrations of total coliforms and faecal coliforms have been reported in

waters of Yamuna River at the Agra Canal mid and quarter stream in Delhi which is

in close proximity to our study area (37). Sewage overflowing from the unlined

35

drains, septic tanks, pit latrine in the study area closer to groundwater source (20)

could presumably be the main reason for contamination as has been observed in other

studies (9), (42-43). The presence of high coliform count including faecal coliforms

indicates the contamination of hand pump water with water borne microbial species

which may be directly attributed to the high frequency of occurrence of water borne

diseases like dysentery, diarrhoea, typhoid, jaundice, etc. as observed and reported in

this area (21). The highest percentage of morbidity and prevalence of diseases has

been reported in slums of Delhi where households have used groundwater for

drinking (44).

CONCLUSION

Resettlement colonies along the Yamuna River have been deprived of basic services

like safe drinking water and a proper sewage disposal system. After evacuation from

slums, these residents are left to the plight of hard living conditions. Being in the

close proximity to the Yamuna River, groundwater aquifers have a high recharge

potential and hence shallow in nature. The groundwater extracted from hand pumps

installed near to the open drains in the present condition is responsible for water borne

diseases in the area, therefore, requiring extensive treatment before its usage for any

activity. Manganese and iron can be removed by oxidation after addition of chlorine

and potassium permanganate to water. These treatment strategies will simultaneously

eliminate coliforms and any other water borne pathogens. Organic matter can be

removed by passing water through candles containing activated charcoal. However,

practicing such procedures will increase the financial burden on the already struggling

daily workers. Supply of safe drinking water and maintaining a regulated sewage

disposal system is the sole responsibility of the Government of Delhi as it does for

other high profile localities.

ACKNOWLEDGEMENTS

Authors are thankful to Delhi University for providing funds under DU Innovative

project scheme to carry out this study. The whole research group is grateful to Dr

Mrigank and Mr Jay Parkash for providing information about the study area and

sincerely acknowledge their cooperation and support during collection of groundwater

samples. We are highly grateful to Prof J. S. Virdi, Department of Microbiology,

University of Delhi South Campus for his able guidance and mentoring during the

project.

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